By Mary Gahan BBC News Online business reporter

A weekly diet of sausage rolls, steak pasties and jam doughnuts ought to play havoc with the waistline.

I do love the steak bake pasties and the sausage rolls

Mike Darrington, Greggs

But after nearly 20 years of tucking into his company's products, Mike Darrington shows no signs of running to fat.

As managing director of the bakery chain Greggs, he believes that tasting the goods is part of his job.

It is also clearly an aspect that he enjoys.

"I like the big selling lines," he says.

"I do love the steak bake pasties and the sausage rolls and the jam doughnuts, Belgian buns..."

Before he works his way through every item of food he sells, I press him for a favourite.

"One product we only sell in Yorkshire - it's a slice, a pastry slice with egg custard and a sort of cream filling.

"It's absolutely mouth-watering, it's naughty but it's a lovely product," he says.

Getting it wrong

Cakes, savouries and sandwiches are what Greggs is all about.

It started as a bakery on Gosforth High Street in Newcastle, floated on the stock market in 1984 and now has a chain of 1,180 shops.

Greggs is targeting more UK towns

It is about to make its first foray overseas. Taking Belgian buns to Belgium, if you like.

It could be argued that the company has been slow to look outside the UK.

But Mr Darrington's style is to be cautious: "We're planning to go at it very sedately.

"We know we'll get it wrong to start with, but we'll learn from it."

Viennoiserie

He hopes to have three or four shops open by the spring, and will judge how successful they are before deciding the next move.

And if the Belgians take to the British sandwich and sausage roll, then France, Holland or Germany could be next.

We experimented with really healthy options and it really killed the business

Mike Darrington

Mr Darrington politely declines to give details of the products that would be on offer in Belgium.

But he says the shops would work in the same way they do in the UK with "core products" as well as local lines - in Yorkshire, for example the local line is that naughty Yorkshire pastry slice.

So Belgians could expect to find Greggs selling the sort of things they are already eating, such as Viennoiserie, alongside sandwiches.

More sausage rolls

I meet Mike Darrington at one of his shops in London's west end.

There is a Starbucks practically next door, which, you might think, would be bad for business.

Not so, says Mr Darrington.

They are serving two very different markets - one specialises in coffee but sells some food. The other specialises in sandwiches and savouries but also sells coffee.

And, apparently, what the take-away public wants more than anything else is sausage rolls.

One hundred million of them were sold last year.

Satisfying customers

So where does Greggs stand on healthy eating?

"We experimented with really healthy options and it really killed the business."

We're very determinedly aimed at the majority of people in the country

Mike Darrington Greggs

The company decided to try using very low-fat mayonnaise at one of its units through the whole range of sandwiches, and sales collapsed.

"We have got to sell things that people want," says Mr Darrington.

"If you try and sell things that people don't want you haven't got a business."

That seems to have been the philosophy all along.

Convenience food

When Greggs floated on the stock market, 40% of its business was selling bread and rolls. That now makes up just 10%.

Part of the change has been driven by competition from the supermarkets.

"We could see the supermarkets were going to beat us on bread and rolls because of convenience," Mr Darrington said.

But, he says, for people who want to come out of their office and buy a take-away sandwich, Greggs is more convenient.

"We believe we are better than most people but we believe we should be a survivor and a thriver."

Neither nasty nor exclusive

He is aware that he might sound a bit complacent, and is quick to say that the company is always looking at what others are doing and making sure it does not lose ground.

Will the Belgians take to jam doughnuts?

And he says that in some towns there are specialist sandwich shops that are really excellent.

But he knows his market. "We're very determinedly aimed at the majority of people in the country.

"We want a �1.50 sandwich that's really going to be good.

"We're neither the cheap and nasty end, nor are we the niche exclusive market end."

Tripping up

Mr Darrington has already overseen the huge growth in the business, including the takeover of Bakers Oven, and he says Greggs will become even bigger.

As well as looking overseas, the group is planning to open hundreds more shops in the parts of the UK it has not yet reached.

But you can be sure that the company will be taking it slowly.

"If you try to do too many things at once you fall over your shoelaces," says Mr Darrington.